Prediction of Intermediate Compound Formation

The formation of intermediate compounds is one of the most important factors affecting the geometry of phase diagrams. Atomic parameter-pattern recognition method is an effective technique dealing with the assessment or prediction problems about the formability of intermediate compounds. 

1 Regularities of formability of intermediate compounds of ionic systems 

Class 1 denotes the samples forming intermediate compound, class 2 denotes the samples without intermediate compound formation, R+ and R2+ denote the ionic radii of monovalent and divalent cations respectively and X+ and X2+ denote the electronegativities of monovalent and divalent metallic elements respectively. 

The data listed in Table 6.1 are treated by support vector classification. It has been found that the published phase diagram of CsBr-CaBr2 system cannot be classified correctly (The published phase 

The methods used are differential thermal analysis (DTA) and X-ray diffraction (including high temperature X-ray diffraction). The experimental result is that there is indeed a 1 1 congruently melting compound (CsCaBra) formed. The melting point of CsCaBrs is 821 C. 

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